The purpose of the conference is to provide a forum for the interaction between scientists representing a broad spectrum of interdisciplinary interests whose studies define the leading edge of research on the mammalian genital tract. The conference is held in a setting which fosters free and trusting exchange of data and new ideas. The conference will not treat female and male reproductive tracts separately but will consider the tracts as the environment for the regulatory cell biology of those processes which underlie fertilization, implantation and early embryogenesis. The conference will focus on the following scientific areas that are relevant to current research on the mammalian genital tract. Drawing the best models from male and female tracts, the participants will engage in a critical re-evaluation of the steroid hormone receptor complex for hormone action. Evidence for validation of alternate mechanisms will be extensively discussed. The role of hormones in the regulation of the relationships between proliferation and differentiation and/or growth of cell populations of the tract will also be studied. Comparisons will be made of coupled vs uncoupled systems of cell division vs differentiation in reproductive tissues and the developing embryo. Attention will be devoted to cell/cell interactions (sperm/egg; trophectoderm/uterus) cell/cell recognition (immunology, implantation, invasion) and a comparison of in vivo vs in vitro microenvironments as the basis of assessing and designing laboratory models.